1. Field of the Invention
The present invention relates to an upper mattress support device, and more particularly to an upper mattress support device for a playpen.
2. Description of the Related Art
A conventional upper mattress support device in accordance with the prior art shown in FIG. 6 is provided on a playpen, which comprises a rectangular frame (50) including four upper support bars (52) and four positioning brackets (54) each secured between two of the four upper support bars (52), a flexible support (55) received in the frame (50) and including an upper periphery enclosing each of the upper support bars (52), an upper mattress (56) received in and supported on the flexible support (55), and two support rods (53) each secured in the frame (50) and each abutting the bottom of the flexible support (55) to support the flexible support (55).
In such a manner, when a baby placed on the upper mattress (56) turns around to concentrate its weight at one side of the flexible support (55), the upper mattress (56) easily wobbles or rocks to incline on the flexible support (55), thereby causing an uncomfortable sensation to the baby. The present invention overcomes the disadvantage of the conventional upper mattress support device.